New Technologies for WMD Detection

by Christopher Hawley

DPJ’s John F. Morton met recently with Chris Hawley to discuss the various systems, devices, and technologies now available, or in the development stage, that can be used by first responders to detect the presence of WMDs (weapons of mass destruction). Following are selected excerpts, slightly edited, from that discussion: Morton: Chris, you have been focusing a lot of your thought and training programs on the use of WMD detection technologies and their relationship to PPE (personal protection equipment).  Remind us why, if you will. Hawley: You know, it goes without saying that it is particularly important for response agencies not only to understand but also how to use WMD detection devices – which are, in addition to protective clothing, the responders’ primary protection against WMD materials. It also is critical to ensure that proper protective clothing is being used, and to determine whether proper isolation and protective measures are being employed.   Morton:  Among the wide variety of detection devices available, what type interests you most? Hawley: The type of handheld portable devices that could be used by response agencies. Morton: Such as? Hawley: Well, those that offer protection against a wide variety of hazards in the basic risk categories: fire, corrosives, and toxics, for example. And radioactive substances. Devices that alert response personnel to potentially hazardous situations.  Devices that enable responders to take a risk-based approach to determine what protective clothing is appropriate, and how much.   Remember, though, that because terrorists have common industrial materials at their disposal and response agencies may encounter ordinary hazardous materials in many situations, these common risk categories I mentioned must always be monitored. A multi-gas instrument – such as one that detects and measures explosive [flammable] atmospheres, oxygen content, carbon monoxide, and hydrogen sulfide – is an important instrument that should always be used.   But some WMD detection devices are not intrinsically safe, so a responder should always know if he or she is in a potentially explosive atmosphere.  If response personnel are wearing air-purifying or powered air-purifying respirators, they have to know the oxygen content to ensure their own safety when they are using these respiratory devices. Another device, which may be a part of the multi-gas instrument – or may be separate – is the photo-ionization detector, also known as a PID.  This device will alert the user to potentially toxic materials in the air. It’s a very sensitive device that can detect very low amounts of those materials. One PID in particular has the ability to detect materials in the parts-per-billion, while others are only at the parts-per-million level. You also can use some simple pH papers, which will alert the user to potentially corrosive atmospheres and let response personnel know about aggressive acids and bases that might be present, which is what pH papers do. The last risk category I mentioned is for the detection of radiation.  Here, response personnel can use a pager-style device or a radiation-detection device.  The pager-style device is easier to use, but responders have to make sure that they use a device that provides a dose rate. Morton: Have we gotten to the point where a handheld portable detection device will give you an on-site analysis comparable to what you get in a laboratory analysis? Hawley: Well, the current detection devices – even though they are becoming more sophisticated – cannot be replaced by laboratory testing. Laboratory tests are the gold standard of analysis – and, I would argue, the only tests that can be used effectively in court cases. I also should mention another issue of importance – namely, that there is no single device that covers all risk categories. In other words, there are chemical and explosive and other types of detection devices, but none that detects radiation, and chemical, and biological [materials], and explosives. Morton: Can you tell our readers a little more about biological detection devices? Hawley:  The area of biological detection is a complicated one, because the current devices are not very quick, and some suffer from accuracy deficiencies. Some work is being initiated on a handheld device that has the potential to detect biological materials in the air, but a workable ready device is several years away. If you want effective biological detection, you should look at a range of devices and technologies. Devices such as a Fourier Transform Infrared Spectroscopy device – what is called an FTIR device – is a good one to start with. A low-cost recommendation is to use a specific protein test. To save responders time and money, I advise going with one that uses a DNA match to perform its testing. To provide confirmation or additional analysis, a PCR [polymerase chain reaction] device is currently the best way to detect materials that are potentially biological in nature.  Another option is to use a handheld assay [HHA] fitted with a reader to test for common biological materials – you always should use a reader with these assays.   When purchasing a PCR or HHA device, you should compare the current models that are on the market. Compare them, for example, by the number and ease of steps required to prepare and analyze a sample. Also compare the running times and the cost of the disposable supplies needed with each. Remember: There is a wide variety of the ways in which samples are prepared for analysis in the machine. You should always divide the suspect material into two separate containers, following proper evidentiary processes. One container is for your field testing. The other one is for the laboratory testing that might be required for a court case.   Morton:  Is there any new cutting-edge biological-detection technology on the horizon that you think is particularly promising? Hawley:  There is one very new device which uses micro-fluidic separation as its sensing technology. That technology could be compared to what is used in high-tech immunoassay testing, because it relies on the migration of impregnated dyes moving through the testing chip.  Various biological materials have retention times in the testing chip that are already known.  The chip is used to compare the retention times of the sample being tested. But the new device I just mentioned – I don’t think I should name it at this time – still needs some additional evaluation to determine its true effectiveness. Morton: What about chemical detection devices? What breakthroughs do you see there? Hawley: In the chemical field, there are some new devices, and there are some devices that have been reformatted or reconfigured to enhance their capabilities. One device is a combination unit that has dual-sensing capabilities – it’s equipped with both an ion mobility sensor, or IMS, and a surface acoustical wave or SAW sensor. Having both of these two technologies is advantageous, because they combine accuracy with the ability to detect low amounts of the product being analyzed. Any device that uses a combination of detection technologies is on the right track, I think, because, considered alone, each detection technology has its own unique deficiencies.  Combining two or more helps minimize the potential false-positive issues. A FTIR unit that is specific to detect unidentified gases is available and can be useful not only in WMD situations but also for more routine cases – sick-building investigations, for example.  On the other hand, a standard FTIR unit may be very helpful in providing the potentialentifications of liquids and solids, but it might not be able to detect gases in an easy fashion.   One manufacturer, I know, provides a Raman Spectroscopy unit that can Bluetooth – wireless – connect to their FTIR unit, which allows for the spectra of the two units to be compared fairly quickly. Raman Spectroscopy devices are new to the emergency-response market and I think will be useful tools in the WMD tool box. Used in combination with FTIR units, they can be of great assistance when dealing with an unidentified material. The FTIR devices themselves have a big advantage in the number of materials they can detect, because they have large libraries. But the Raman devices have a different advantage in that the material [being detected and/or analyzed] can be read through a glass or plastic container.  You have to remember: Like many other detection devices, the FTIRs and the Raman units both have slight limitations in the fact that they are not 100 percent accurate. They are important tools but should never be used alone. Morton: What do you consider to be the cutting-edge technology in chemical detection? Hawley: There is one device that is fitted with a new variety of detection sensors and uses a miniature chromatograph column in combination with a SAW sensor.  It has fairly low detection limits – in the parts-per-billion range, and that would be very useful. Much like its cousin, though, the biological detection device that uses micro-fluidics, this device needs some additional testing and evaluation before we can judge its true abilities. Morton: Chris, you have commented a couple of times about the need for responders to smart shoppers.  What specific advice can you give our readers in this area? Hawley:  Always try before you buy. And remember: You are the customer.  If you are going to invest thousands of dollars in a detection device, make sure it is one that your lowest-echelon people can operate.  If only your best responders can operate the device, you are setting yourself up for failure. So step outside your normal purchasing box and look at all the vendors who are selling various devices and technologies. Compare the devices side by side, counting the number of steps required to prepare a sample, for example. In short, determine which device is the easiest to use and offers the best range of options. One or two other things to remember: First, devices that can be used in everyday hazardous situations are usually better to buy than devices that have WMD capabilities only. Also, compare the set-up times and the cost of the disposable supplies needed, as well as the shelf lives of those supplies. Having a device in your tool box that does not require instructions for use is advantageous, and having one that requires only a minimal set-up should be a prime consideration as well.   Most important of all, though: Ask the vendors lots of questions.  Call them on their claims.  Ask about problems people may have been having with the device. Also, ask for references and follow up by calling those references. It also would be a goodea to study the independent test results that many manufacturers have available. Examine the raw data. Then go back again with this data and ask more questions of the vendor. Morton: Chris, that’s really great advice. Thank you so much for your time, and for sharing your expertise with our DomPrep readers. Chris Hawley, a firefighter, a HazMat responder, and a former special operations coordinator for teh Baltimore County (Md.) Fire Department, is now a project coordinator for the Computer Sciences Corporation with responsibilities for various WMD-related programs throughout Eastern Europe, Central Asia, and other parts of the world.  The author of five texts on hazardous materials and terrorism response, he also has written numerous magazine and trade-journal articles.